Vidur Neeti is a chapter in the Udyoga Parva of Mahabharata and it contains the advice given by Vidura to the blind king Dhritarashtra
My Lord, the people who are unable to sleep are:
A man who lusts after the wife of another cannot sleep.
A thief cannot sleep.
A man who has lost all his wealth cannot sleep, or one who thinks all his wealth will be lost.
A person afflicted with avarice, greed and jealousy cannot sleep.
An unsuccessful man cannot sleep.
A weak man oppressed by as strong man cannot sleep.
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